D-dimer as an independent predictor for poor outcome after aneurysmal subarachnoid hemorrhage

After aneurysmal subarachnoid hemorrhage (SAH), elevated D-dimer levels have been associated with poor clinical condition and outcome. We tested prospectively whether D-dimer values affect outcome after SAH independently of severity of bleeding.

Previous diseases, and clinical as well as radiological variables, were recorded for 136 patients with SAH admitted within 48 hours after bleeding. Plasma D-dimer was measured in the morning after aneurysm occlusion and at discharge 10 to 12 days after SAH. Factors predicting poor outcome according to the Glasgow Outcome Scale at 3 months after SAH and appearance of cerebral infarction were tested with multiple logistic regression.

Patients with poor outcome had higher D-dimer values than did those with favorable outcome: after surgery, a median 1250 (25th and 75th percentiles 675 and 2900) microg/L versus 720 (350 and 1119) microg/L (P=0.001); and at discharge, 1150 (624 and 2875) microg/L versus 360 (330 and 600) microg/L (P<0.001), respectively. In repeated-measures ANOVA, D-dimer decreased more rapidly (P=0.022) in those with favorable outcome. After simultaneous adjustment for several factors affecting outcome, plasma D-dimer after surgery remained a significant predictor for poor outcome (odds ratio, 1.63 per mg/L; 95% CI, 1.03 to 2.60; P=0.038) but neither for delayed ischemia nor, on follow-up computed tomography in survivors, for cerebral infarction.

Elevated plasma D-dimer after admission independently predicts poor outcome, suggesting that prolonged excess thrombin generation may impair outcome. Repeated high plasma D-dimer values can be useful in discovering patients at increased risk for poor outcome.